Never state the nature of the trick you are about to perform.
Make it a rule never to repeat a trick the same evening unless you have
acquired a different way of showing it. In fact, it is advisable to
learn several methods of presenting the same trick.
Talk as much as possible and make your "patter" lively, but do not try
to be funny unless you are naturally humorous; and, above all, avoid
allusions to politics, religion, or any subject about which there may be
a diversity of opinion among your audience.